Ecological Costs and Benefits of Teak Defoliator (&lt;i&gt;Hyblaea puera &lt;/i&gt;Cramer) Outbreaks in a Mangrove Ecosystem

Arun P R,Maya V Mahajan

doi:10.5923/j.ms.20120205.02

Abstract

The Teak defoliator moth (Hyblaea puera) is a well-known pest causing significant economic losses on tim- ber production fro m teak p lantations during their seasonal outbreaks. Apart fro m Teak, it also attacks an alternative host plant, Avicennia marina, a prominent mangrove tree species abundant along the west coast of India, causing severe and extensive defoliation of Mangroves. However, the ecological ro le of this pest species in the mangrove ecosystem appears to be complex and is much less understood. Here we report the lesser known ecological aspects of Hyblaea infestation fro m the Mangrove ecosystem of Thane creek area of Mu mbai, Maharashtra, India, based on our field observations. Beyond the apparent feeding damage and defoliation caused by the Hyblaea caterpillars, there are quite a few positive ecological ser- vices that these pests are rendering to the mangrove system, especially in the context of mangroves of Mumbai. These in- clude pro motion of mangrove diversity, nutrient enrich ment and boosting of fishery yield. A possibility of genetic diver- gence between the Hyblaea populations feeding on Teak and Avicennia is also indicated based on obvious differences in behavioural and life history traits between the populations of this pest in Teak plantations and Mangroves. The paper thro ws up an apparent conservational dilemma o f whether Hyblaea puera in the context of Mangrove ecosystem is a 'pest to be controlled or a species to be conserved' ?.

Highlights

The mangrov e fo rests along th e Mu mb ai coast (M aharashtra, India) gets affected by the remarkable outbreaks of the moth Hyblaea puera (Order: Lep idoptera; Family: Hyblaeidae)
Ho wever there is very litt le in format ion on these aspects fro m the Mangroves, where this pest is found on an alternative host in Grey M ang ro ves (Avi cenn ia sp .) and has ing en ious ly adapted its life-h istory traits to suit the micro environ mental conditions of the mangroves, which are different fro m that of the Teak p lantations
The paper examines the ecological roles played by a Lepidopteran pest species, the Hyblaea puera, during its outbreaks in the mangrove forests of Mumbai region

Summary

Introduction

The mangrov e fo rests along th e Mu mb ai coast (M aharashtra, India) gets affected by the remarkable outbreaks of the moth Hyblaea puera (Order: Lep idoptera; Family: Hyblaeidae). Ho wever there is very litt le in format ion on these aspects fro m the Mangroves, where this pest is found on an alternative host in Grey M ang ro ves (Avi cenn ia sp .) and has ing en ious ly adapted its life-h istory traits to suit the micro environ mental conditions of the mangroves, which are different fro m that of the Teak p lantations. The outbreak of this pest causes several beneficial and pos itive impacts on the ecosystem and

Background

Ecological costs and benefits

Impact on Biodi versity

Findings

Conclusions